2 Allergy Free Pillow Covers standard size. These pillow covers are made from a specially treated polycotton that stops the growth of mold, mildew, fungus and bacteria. Many pillows become infested and cause allergies, sneezing, morning headaches, sinus congestion, itchy eyes and respiratory problems. The anti-microbial treatment applied to the covers prevents unwanted mold and bacterial growth and keeps the pillow deodorized and always fresh. Size standard.